Months Of Functional Loading Research Articles

Implant stability and clinical outcome between implant placement using internal sinus floor elevation with alloplastic bone material grafting and without grafting: A 1-year randomized clinical trial.

To compare implant stability and clinical outcome in implant placement between osteotome sinus floor elevation (OSFE) with biphasic calcium phosphate (BCP) which consisted of 30% of hydroxyapatite (HA) and 70% of beta-tricalcium phosphate (β -TCP) grafting material and OSFE without using bone grafting material. The research questions is whether the BCP provides any benefit in OSFE or not. Thirty patients (30 implants) with a single edentulous area of upper premolar or molar were randomly separated into OSFE with BCP (n = 15) and OSFE without grafting (n = 15). The patients were reevaluated 3, 6, 9, and 12months after implant loading. The clinical assessments (implant stability quotient (ISQ), implant survival-failure rate, and surgical complication) were analyzed. Together with radiographic assessments in 2D (endo-sinus bone gain (ESBG), mean marginal bone change (MMBC)) and 3D (endo-sinus bone gain in CBCT (ESBG-CT)) were evaluated, with a mean follow-up time of at least 12months of functional loading and prosthetic complication. 20 remaining implants (OSFE with BCP, n = 10; OSFE without grafting, n = 10) were analyzed. Mean ISQ was 79.18 3.43 in 1-year follow-up (ISQ; OSFE with BCP = 78.72 3.46, OSFE without grafting = 79.65 3.52). ISQ in both groups increased steadily without significant differences in each follow-up. (p = 0.56). In radiographic evaluation, at 6-, 9-, and 12-month, OSFE without grafting group showed statistically significant lower MMBC (p < 0.05). The 1-year clinical results showed that 2 implants failed in OSFE with BCP, and 1 implant failed in OSFE without grafting. Graft material "BCP" (HA30:TCP70) coupled with OSFE presents no extraordinary benefit in implant stability, clinical and radiographic outcome in 1-year follow-up. Clinically, OSFE with grafting materials provides no additional benefit. TCTR20210517008 (date of registration: May 17, 2021).

Peri-implantitis in patients without regular supportive therapy: Prevalence and risk indicators

ObjectivesTo determine the prevalence of peri-implant diseases in patients treated in a university setting without a regular peri-implant supportive therapy schedule, and to identify the risk indicators associated with peri-implantitis.Material and methodsA retrospective cohort study was made of patients with dental implants with at least 12 months of functional loading who did not receive regular peri-implant supportive therapy. Patient- and implant-related variables were retrieved, and clinical and radiological examinations were performed. Descriptive and bivariate analyses and multilevel logistic regression analyses were performed to identify factors associated with peri-implantitis.ResultsA total of 213 implants in 88 patients were analyzed. The patient-level prevalence of peri-implantitis and peri-implant mucositis was 26.1% (95%CI: 16.7%—35.5%) and 44.3% (95%CI: 34.0%—54.6%), respectively. Peri-implant diseases were significantly more frequent when the width of the keratinized mucosa was < 2 mm (OR = 5.26; 95%CI: 1.24—22.26; p = 0.024), and when there was 12 month post-loading bone loss (OR = 2.96; 95%CI: 1.35—6.52; p = 0.007).ConclusionsPeri-implantitis is a common finding in patients without regular peri-implant supportive therapy (prevalence 16.7–35.5%). A thin peri-implant keratinized mucosa (< 2 mm) and a higher degree of bone remodeling after loading seem to be the main risk factors for peri-implantitis in this patient profile.Clinical relevancePatients who do not engage in supportive peri-implant maintenance have a higher risk of peri-implantitis. A thin keratinized mucosa and bone loss during the first year of loading are predisposing factors for peri-implantitis.

The influence of vertical ridge augmentation techniques on peri-implant bone loss: A systematic review and meta-analysis.

The primary aim of this systematic review was to investigate and compare the outcomes of different vertical ridge augmentation (VRA) techniques in relation to peri-implant bone loss (PBL), after at least 12 months of functional loading. The search was conducted to find all the studies about VRA and measurements of PBL with at least 12 months follow-up. Three pairwise meta-analysis (MA) was performed to completely evaluate the outcomes. A total of 42 studies were included, of which 11 were randomized clinical trials (RCTs). RCTs were available only for guided bone regeneration (GBR), onlay, and inlay techniques. The weighted mean estimate (WME) of PBL value was found to be 1.38 mm (95% confidence interval [95% CI]: 1.10-1.66) after a mean follow-up of 41.0 ± 27.8 months. GBR, Inlay, Onlay, osteodistraction, and SBB represented in weight 32.9%, 30.6%, 25.0%, 7.6%, and 3.9%, respectively; and their WME (95% CI) were 1.06 (0.87-1.26) mm, 1.72 (1.00-2.43) mm, 1.31 (0.87-1.75) mm, 1.81 (0.87-1.75) mm, and 0.66 (0.55-0.77) mm, respectively. Among the secondary outcomes, the analysis was conducted for vertical bone gain, healing complication rate, surgical complication rate, implant survival, and success rate. The primary findings of the meta-analysis, based on the changes between final and baseline values, showed that the peri-implant bone loss could be influenced by the type of intervention but there is a need to evaluate in RCTs the behavior of the peri-implant bone levels after long-term follow-up for all techniques.

A three-in-one alveolar process reconstruction protocol for maxillary molar sites with severe residual bone height deficiency: A proof-of-concept pilot study.

Implant placement in maxillary molar sites with severe height deficiency often requires multiple surgeries, which was time-consuming, invasive, and subject to serious postoperative complications. To introduce and assess a three-in-one technique (extraction, alveolar ridge preservation [ARP], and sinus elevation) for augmenting deficiency maxillary molar alveolar ridges. Fourteen patients with severe posterior maxillary ridge height deficiency underwent extraction, sinus elevation via an intrasocket window and ARP using sticky bone and then covered with acellular dermal matrix (ADM). Primary closure was intentionally not obtained. Cone-beam computed tomography and periapical radiography were used to measure dimensional ridge changes over time. Bone biopsies were taken at implant placement 7-21 months after surgery, which proceeded without additional grafting. Peri-implant soft tissue was assessed after 8-12 months of functional loading. Maxillary molar sites (13 first molars, 1 second molar) with a mean sinus floor height of 1.73 ± 0.86 mm and mean buccal plate thickness of 1.62 ± 1.15 mm were elevated and grafted. Immediately after surgery, the mean sinus floor height was 14.03 ± 1.97 mm and the alveolar thickness at virtual implant platform level was 12.99 ± 1.88 mm. After 5-9 months healing, those measurements decreased by 2.45 ± 1.73 mm (p= 0.000) and 3.88 ± 3.95 mm (p= 0.006), respectively. Healed ridges were composed of 18.74% ± 4.34% mean vital bone and 19.08% ± 9.10% mean residual graft. After 8-12 months of functional loading, the peri-implant tissue appeared healthy, and there was a mean marginal bone loss of 0.12 ± 0.11 mm. For maxillary first molar sites with severe sinus floor height deficiency, this minimally invasive three-in-one treatment allows for uncomplicated implant placement and short-term functional stability.

A temporospatial histomorphometric analysis of bone density adjacent to acid-etched self-tapping dental implants with an external hexagon connection in the female baboon.

To characterize osseointegration as the percent of bone-implant contact (%BIC) along the surface (0.0mm) as well as at surface profiles 0.5mm and 1.0mm lateral to the implant, determining any differences between early occlusally loaded and non-loaded implants. In ten adult female baboons, 120 dental implants were randomly placed in opposing mandibular and maxillary locations. Eighty sites had two groups of healing (no load) of either 1 (n = 40) or 2 (n = 40) months leading to 3months of functional loading. These sites received full acid-etched surface implants. The 40 control implants represented healing only periods (no load) for 1 (n = 10), 2 (n = 10), 4 (n = 10), and 5 (n = 10) months. These implants were of a vertically split surface texture design (acid-etched and machined). Block sections and photomicrographs were obtained. Blinded histometric analyses determined the %BIC via a superimposed template. The unloaded groups (1, 2, and 4months) had higher %BIC compared to the 5-month group (p < 0.0001). The loaded groups exhibited mean bone densities of 59.2% and 55.5% (1-month healing at 0.5mm and 1.0mm, respectively) and 61.0% and 57.1% (2-month healing at 0.5mm and 1.0mm, respectively) with no significant difference between healing time (p = 0.4118). There was a lateral increase in %BIC in the loaded compared to unloaded groups. The decrease in bone densities at the 5-month unloaded group suggests that there is a critical earlier time period when dental implants should be placed into functional load.

Implants with a Laser-microgrooved Collar Placed in Grafted Posterior Maxillary Extraction Sockets and in Crestally Grafted Sinuses: a 5-Year Multicentre Retrospective Study.

ABSTRACTObjectivesThe aim of this retrospective multicentre cohort study was to compare clinical outcomes, soft tissues conditions and differences in marginal bone loss between implants with a laser-microgrooved collar placed in posterior maxillary extraction sockets grafted by 4 to 5 months, and in posterior maxillary pristine bone (spontaneously healed posterior maxillary extraction sockets) by means of osteotome-mediated sinus floor elevation, over a period of 5 years after functional loading.Material and MethodsPatients of Group 1 underwent extractions with sockets preservation using porcine-derived bone, covered with collagen membrane. Group 2 underwent extractions without socket preservation. Patients of Group 1 received implants in grafted sites, and Group 2 received implants in spontaneously healed bone using a maxillary sinus lift with crestal approach.ResultsOver the observation period, the overall clinical success rate in Group 1 and Group 2 was 98% and 100%, respectively, with no differences between the procedures and implants used. Cumulative radiographic marginal bone loss ranged from 0.03 to 0.39 mm after 60 months of functional loading. There were no statistically significant differences in marginal bone loss between short and standard-length implants placed in grafted extraction sockets and in pristine bone.ConclusionsShort and standard implants with a laser-microgrooved collar, placed in posterior maxillary extraction sockets grafted by 4 to 5 months, and in posterior maxillary pristine bone (spontaneously healed posterior maxillary extraction sockets) by means of osteotome-mediated sinus floor elevation, exhibited no statistical difference in success rate, clinical parameters and marginal bone loss.

Comparison of Marginal Bone Loss Around Axial and Tilted Implants: A Retrospective CBCT Analysis of Up to 24 Months.

This clinical study retrospectively analyzed cone beam computed tomography (CBCT) images to determine the potential influence of implant inclination on peri-implant marginal bone loss after 18 to 24 months of functional loading. Twenty-five consecutive patients presenting with an edentulous or partially edentulous maxilla or mandible and an adequate bone volume for receiving oral implants were selected for analysis of the marginal bone loss around tilted and/or axial implants. The study population included patients rehabilitated with Toronto bridges (TBs), fixed partial dentures (FPDs), or single crowns (SCs) on axial and/or tilted implants. The primary outcome was the CBCT analysis of peri-implant marginal bone level change, depending on inclination of implants and type of prostheses. The secondary outcome was analysis of survival and success rates of tilted and axial implants. A significant difference was observed for peri-implant buccal bone loss (mean of axials 0.42 ± 0.06; mean of tilted 0.70 ± 0.09) (P = .009). The difference in peri-implant lingual/palatal/mesial/distal bone loss was not significant between axial and tilted implants (P > .05). No significant difference was observed between the marginal bone level and the type of prostheses for both tilted and axial implants in all the assessed sites (P > .05). The success rate for both tilted and axial implants was 100%, and no complications were observed for all the prosthetic rehabilitations, with a 100% survival rate. Compared to axial implants, tilted implants showed a significant statistical difference for peri-implant buccal bone loss, but no other differences were observed for peri-implant bone loss or for implant survival and success rate. Fixed partial or total rehabilitation using tilted or axial implants, or with tilted and axial implants, could be a reliable technique with advantages to patients and operators.

Immediate Nonsubmerged Custom Root Analog Implants: A Prospective Pilot Clinical Study.

To evaluate the feasibility of a commercially available immediate root analog implant system Replicate (Natural Dental Implants). Five consecutive patients in need of an implant in the premolar region were recruited for this pilot study. Following clinical examination, a cone beam computed tomography scan was made and the dental impressions digitized. On the basis of the superimposition of these datasets, a three-dimensional (3D) envelope was created for the selected tooth. Subsequently, the tooth root at the prospective implant site was segmented to create a 3D surface, and the obtained mesh data were used as the basis for designing a single-piece root analog implant within the 3D envelope. The designed root analog implant was fabricated using a five-axis computer-aided manufacturing machine. The root analog implants were inserted following flapless minimally invasive root extraction. Following 3 months of uninterrupted healing, definitive restorations were fabricated. Peri-implant clinical and radiographic measurements were obtained up to 12 months follow-up. All patients functioned well following 12 months of functional loading. Within one patient, one of the two root analog implants failed early. Peri-implant clinical and radiographic measurements demonstrated a stable situation after 12 months of functional loading. A novel digital approach for immediately restoring single teeth using root analog implants was introduced. In the future, long-term evaluation of the root analog implant technique is necessary to evaluate the success and survival of implants that were inserted using this technique.

Computer‐Guided Immediate Implant Placement and Predigitally Designed Immediate Provisionalization

IntroductionImplementation of digital technology in patient care has allowed precise and personalized implant restorations to be delivered with unprecedented speed. This case report demonstrates that through digital planning, successful guided placement of an immediate implant can be achieved, including bone grafting and immediate provisionalization, using a predesigned and prefabricated restoration.Case PresentationA healthy 38‐year‐old female patient with high esthetic demands presented with an unrestorable maxillary left first premolar. Main challenges in this case included the presence of an impacted adjacent second premolar and the desire of the patient for a fixed provisional prosthesis. The treatment plan involved extraction of the tooth, computer‐guided immediate implant placement, and immediate provisionalization with a digitally designed, presurgically fabricated crown. After immediate delivery of the provisional crown, which facilitated sculpting of the peri‐implant soft tissue, minimal adjustment was required, and there was no need for suturing to seal the grafted socket. After delivery of the final restoration and 10 months of functional loading, evaluation of the implant and restoration revealed stable crestal bone levels with an esthetically pleasing result and high patient satisfaction.ConclusionsDigital technology can play a significant role in implant therapy. Select cases can benefit from the digital workflow to facilitate guided immediate implant placement and delivery of a digitally prefabricated provisional restoration. Further studies are needed to optimize the generalizability of this approach.

Alveolar Bone Resorption Evaluation Around Single-piece Designed Bicortical Implants, Using Immediate Loading Protocol, Based on Orthopantomographs

Abstract Background: Inserting dental implants in severely atrophied jawbones is a great challenge for the dental practitioner. There are an increasing number of patients who choose dental implantanchored prosthetic restorations despite compromised bone quality and quantity. There have been numerous attempts in adapting implant design for the atrophic crestal bone. One-piece, needle-type basal implant design is a typical design for these cases. These implants are inserted in the remaining compact bone located in the basal aspect of the jawbones. If high primary stability is achieved, these implants are used for immediate loading protocol. From many points of view, this technique is based on contradictory principles compared to classic implant surgery and loading protocols. The aim of this study was to investigate the long-term success of basal one-piece short-diameter dental implants used for immediate loading protocol. Materials and methods: A total of 56 dental implants were included in this study. Peri-implant bone loss was measured on orthopantomographs. Bone resorption was measured in millimeters in the first 6 and 12 months of functional loading. Results: There were no failing implants in this period; average bone resorption was 1.59 mm after 6 months of functional loading and 2.05 mm after 12 months. Bone resorption was slightly higher in the mandible than in the maxilla. Conclusions: Immediate implant loading protocol might be an attractive solution for fixed fullarch restoration using short-diameter one-stage basal implants, but long-term effects require further investigations.

Volumetric Bone Measurement Around Dental Implants Using 3D Image Superimposition: A Methodological and Clinical Pilot Study.

This study describes the development of a methodology for using three-dimensional (3D) image superimposition to measure volumetric changes in bone level around dental implants in comparison with linear measures. The sample was comprised of 46 dental implants of 6-mm length and 4.1-mm diameter placed in the posterior maxilla and posterior mandible in 20 patients. All implants received screw-retained single crowns. Radiographic images were taken using cone beam computed tomography (CBCT) and digital periapical radiography after implantation and after 12 and 24 months of functional loading (after crown installation). Tridimensional reconstructions of the bone perimeter closest to the implant were developed, superimposed, and volumetrically measured. Linear measures of bone levels were recorded in periapical radiography images. A multilevel regression model tested volumetric and linear bone loss. The mean peri-implant linear bone loss for the first and second years was 0.2 ± 0.4 mm and 0.1 ± 0.2 mm, respectively, and the mean volumetric bone loss for the first and second years was 7.2 ± 6.1 mm³ and 6.4 ± 7.8 mm³, respectively. It was estimated that an increase of 1 mm of linear bone loss was associated with a mean volumetric bone loss of approximately 14 mm³ (P < .001). The findings showed that linear and volumetric bone loss measures are related. Measuring volumetric bone changes around implants is possible provided that the CBCT images have proper contrast and sharpness, particularly around the implant outline. Improvements in image quality and in the filters for bone tissue detection would be important for this methodology to be made faster and used clinically.

Histopathological comparison of healing after maxillary sinus augmentation using xenograft mixed with autogenous bone versus allograft mixed with autogenous bone

To compare the clinical and histologic outcomes of two different grafting materials (allograft and xenograft) when combined with autogenous bone and covered with a collagen membrane for sinus augmentation. A parallel case series of fourteen patients in need of a unilateral sinus augmentation was evaluated in this study. Seven patients received a graft composed by autologous cortical bone (ACB) and anorganic bovine bone in a ratio of 1:1; the other seven patients received ACB mixed with an allograft in the same ratio. Bone biopsies were obtained 6months after sinus augmentation at the time of implant placement. Comparative histomorphometrical, histopathological, and immunohistochemical analyses were conducted and statistically analyzed. After 12months of functional loading, all implants in both groups were clinical and radiographically successful. Histomorphometrically, although the initial bone formation was not significantly different between groups (new mineralized tissue: 41.03(12.87)% vs. 34.50(13.18)%, p=.620; allograft vs. xenograft groups), the graft resorbed faster in the allograft group (remnant graft particles: 9.83[7.77]% vs. 21.71[17.88]%; p=.026; allograft vs. xenograft groups). Non-mineralized tissue did not statistically differ either (49.00[14.32]% vs. 43.79[19.90]%; p=.710; allograft vs. xenograft groups). The histologic analyses revealed higher cellular content, four times more osteoid lines, and higher vascularization in the xenograft group. Musashi-1 (mesenchymal stromal cell marker) was also more intensively expressed in the xenograft group (p=.019). Both composite grafts generate adequate substratum to receive dental implants after healing. Compared with the xenograft composite, allograft composite shows faster turnover and a quicker decrease in biological action after 6months.

Soft Tissue Changes Around Immediately Placed Implants: A Systematic Review and Meta-Analyses With at Least 12 Months of Follow-Up After Functional Loading.

Immediate implant placement (IIP) is predictable but can lead to esthetic challenges, including midfacial recession (MFR) and papillary height (PH) loss. The aim of this systematic review is to examine the effect of IIP on MFR and PH after at least 12 months of functional loading. Literature review of the Cochrane and MEDLINE electronic databases and hand search up to January 2016 identified eligible studies. Four reviewers independently assessed data quality and methodology. A total of 106 articles satisfied the inclusion criteria. Twelve studies qualified for three meta-analyses. MFR was slightly less in conventional implant placement (CIP) than in IIP, but the result was not statistically significant (mean difference [MD] -0.064 mm; P = 0.687). Similarly, there was better PH maintenance in CIPs, with statistical significance for distal PH (DPH) only (cumulative PH: MD -0.396, P = 0.010; DPH: MD -0.765, P <0.001; mesial PH [MPH]: MD -0.285, P = 0.256). MFR was slightly less in IIP with thick versus thin biotypes, but not statistically significantly different (MD -0.373, P = 0.243). Pooled data showed statistically significantly less MFR and better PH maintenance in IIP with thick biotype (MFR: MD -0.478, P <0.001; cumulative PH: MD -0.287, P <0.001; MPH: MD -0.288, P <0.001; DPH: MD -0.310, P <0.001). Non-significantly less MFR (MD 0.253, P = 0.384) and significantly better PH maintenance were found in IIP with immediate provisionalization versus conventional restoration (MD -0.519, P = 0.028). IIP in thick biotype and with immediate provisionalization had less MFR and better PH than IIP in thin biotype or with delayed restoration. However, these findings should be interpreted with caution due to high heterogeneity, which was calculated using comprehensive meta-analysis statistical software that took into account sample size and different treatment groups, and limited qualified studies.

Resorbable vs Non-resorbable Barriers with Immediate Implantation after Functional Loading under Overdenture

ABSTRACT Aim The aim was to evaluate the bone height and bone density of the peri-implant area with resorbable and non-resorbable barriers as guided tissue regeneration with immediate implants after functional loading under mandibular overdenture. Materials and methods Eight male patients (the age ranged between 45 and 60 years old), who had the upper jaw as fully edentulous and the lower jaw with only two remaining canines and indicated for extractions, were selected. Each patient received two immediate implants after extraction of remaining canines and were divided into two groups: Group I: The left side received non-resorbable barrier and group II: The right side received resorbable barrier. Radiographic evaluation was done for marginal bone height loss and bone density immediately after overdenture insertion and 6 months later. Results Mean marginal bone loss with non-resorbable barriers was 0.7 ± 0.16 mm and with resorbable barrier was 0.6 ± 0.1 mm, with nonsignificant difference between the two groups. There was significant increase in bone density with resorbable barrier after 6 months of functional loading, with significant difference between the two groups. Conclusion There was no difference in marginal bone height changes between resorbable and non-resorbable barriers with immediate implant under overdenture. However, after 6 months of functional loading, bone density increased with the use of resorbable barrier over non-resorbable barriers. Using of resorbable barrier with immediate implantation did not require second stage surgery for removing the barrier as with the non-resorbable one. How to cite this article Elkholy S, Elcharkawi H. Resorbable vs Non-resorbable Barriers with Immediate Implantation after Functional Loading under Overdenture. Int J Experiment Dent Sci 2017;6(2):74-79.

Clinical evaluation with 18 months follow-up of new PTTM enhanced dental implants in maxillo-facial post-oncological patients

The aim of this study is to present 18 months follow-up results of porous tantalum trabecular metal-enhanced titanium dental implant (PTTM) in implant supported prosthesis in post-oncological patients. A total of 25 PTTM implants were placed in each jaw of 6 patients that met specific inclusion and exclusion criteria. Resonance Frequency Analysis (RFA) was conducted and Implant stability was recorded in ISQ values (Osstell ISQ, Osstell AB, Goteborg, Sweden) at implant placement and after 2,4,6,12 and 18 months of functional loading. Mean bone loss was also evaluated at the same interval of time on each periapical radiographs, bone levels were calculated by measuring the distance from the implant shoulder to the first bone to implant contact. Cumulative implant survival rate is 100% (n=25/25) to date and mean ISQ values recorded were: 72.14±5.61 (range= 50-81) at surgery, 64.39±8.12 (range=44-74) after 2 months, 74.26±7.14 (range=44-74) after 4 months, 76.84±7.65 (range=60-83) after 6 months, 78.13±4.14 (range=64-84) after 12 months and 80.22±6.23 (range=68-89) after 18 months of functional loading. Mean crestal marginal bone loss was 0.19±0.25 mm after 2 months of functional loading on periapical radiographs, 0.22±0.4 mm at 4 months, 0.3±0.46 mm at 6 months, 0.57±0.62 at 1 year and 0.64±0.60 mm after 18 months. The results of this study, even if limited by the number of implants placed indicate that PTTM dental implants have a clinical efficacy in prosthetic rehabilitation of post-oncological patients, due to trabecular structure of the porous Ta metal that increases bone-implant connection values.

Clinical and radiographic evaluation of narrow-diameter titanium-zirconium implants in unilateral atrophic mandibular distal extensions: a 1-year pilot study.

The use of endosseous dental implants has led to more sophisticated fxed options when considering treatment of patients with distal extensions. The use of narrow-diameter implants may reduce the necessity for bone augmentation. The mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable. The purpose of this study was to evaluate clinically and radiographically the performance of narrow-diameter bone level implants made from titanium-zirconium alloy (TiZr, Roxolid(TM)) in restoring unilateral atrophic mandibular distal extensions with fxed dental prostheses. Twenty partially edentulous patients with unilateral atrophic mandibular distal extensions received two 3.3 mm diameter bone level TiZr implants (Straumann AG, Basel, Switzerland). The two implants were restored with 3-units ceramo-metal fxed partial dentures. Standardized clinical and radiographic parameters (survival rate, probing pocket depth and marginal bone loss) were evaluated at the time of the completion of the prosthetic treatment (baseline) and after 3, 6 and 12 months of functional loading. Prosthetic complications were also assessed. The survival rate for narrow-diameter bone level TiZr implants was 100% after 1 year of functional loading. There were no statistically significant differences between the values of probing pocket depth over the follow-up period. All implants showed less than 1 mm of marginal bone loss at the end of the follow-up period. Within the limitations of this 1-year pilot study, the use of narrow-diameter bone level TiZr implants appears to be predictable in restoring the unilateral atrophic mandibular distal extensions. This type of implants meets established success and survival criteria after 1 year.

Marginal bone loss around implants placed in maxillary native bone or grafted sinuses: a retrospective cohort study

To assess differences in marginal bone loss around implants placed in maxillary pristine bone and implants placed following maxillary sinus augmentation over a period of 3years after functional loading. Two cohorts of subjects (Group 1: Subjects who received sinus augmentation with simultaneous implant placement; Group 2: Subjects who underwent conventional implant placement in posterior maxillary pristine bone) were included in this retrospective study. Radiographic marginal bone loss was measured around one implant per patient on digitized panoramic radiographs that were obtained at the time of prosthesis delivery (baseline) and 12, 24, and 36months later. The influence of age, gender, smoking habits, history of periodontal disease, and type of prosthetic connection (internal or external) on marginal bone loss was analyzed in function of the type of osseous support (previously grafted or pristine). A total of 105 subjects were included in this study. Cumulative radiographic marginal bone loss ranged from 0mm to 3.9mm after 36months of functional loading. There were statistically significant differences in marginal bone loss between implants placed in grafted and pristine bone at the 12-month assessment, but not in the subsequent progression rate. External prosthetic connection, smoking, and history of periodontitis negatively influenced peri-implant bone maintenance, regardless of the type of osseous substrate. Implants placed in sites that received maxillary sinus augmentation exhibited more marginal bone loss than implants placed in pristine bone, although marginal bone loss mainly occurred during the first 12months after functional loading. Implants with external implant connection were strongly associated with increased marginal bone loss overtime.

Immediate Loading of Implants Placed Simultaneously with Sinus Membrane Elevation in the Posterior Atrophic Maxilla: A Two‐Year Follow‐Up Study on 10 Patients

Clinical studies on immediate loading of implants in the posterior atrophic maxilla are rare. The study aims to evaluate immediate loading of implants placed with sinus membrane elevation without additional grafting material for bone augmentation of the maxillary sinus floor. The study group comprised of 10 patients in whom a total of 10 maxillary sinus floor augmentations were performed. A total of 21 dental implants (1 to 4) were inserted through the residual bone to protrude into the maxillary sinus under the elevated sinus membrane. The implant site was underprepared to improve primary stability. All the implants were inserted with a torque insertion no less than 20 Ncm. Implants were loaded immediately after surgery with a screw-retained temporary acrylic restoration. Intraoral X-rays were taken at implant insertion, after 6 months loading, and after 1st and 2nd year of loading. Resonance frequency analysis (RFA) was performed at the time of initial placement and after 6 months of functional loading. RFA after implant insertion gave an implant stability quotient (ISQ) level with a range from 62 to 72. All implants remained clinically stable during the follow-up period of 2 years. Radiography demonstrated on average 5.7 ± 3.4 mm of intrasinus new bone formation after 6 months of implant loading. RFA measurements showed ISQ mean values of 67 (range: 62-72) and 68 (range: 62-71) at placement and after 6 months of loading, respectively. Within the limits of this case series report, it is concluded that maxillary sinus membrane elevation with simultaneous placement and immediate loading of implants without the use of any additional grafting material shows predictable results after 2 years of functional loading. Moreover, evidence of intrasinus bone formation around the implants was found in all patients. Further studies are needed to study the influence of immediate loading on the mineralization of bone forming at dental implant sites.

Graft Shrinkage and Survival Rate of Implants After Sinus Floor Elevation Using a Nanocrystalline Hydroxyapatite Embedded in Silica Gel Matrix

The aims of this study were (1) to evaluate the vertical shrinkage percentage of nanocrystalline hydroxyapatite embedded in silica gel used for maxillary sinus floor elevation (SFE) and (2) to determine the survival rate of the implants 1 year after placement in the healed grafted sinuses. Eleven maxillary sinuses were augmented in eight patients with NanoBone. After a healing period averaging 14.42 months, 19 implants were placed and followed up with clinical and radiographic evaluation. Panoramic radiographs were taken immediately after SFE and at 12 months after grafting. Measurements of changes in height were made by a computerized measuring technique using an image editing software. The mean graft height shrinkage percentage at 12 months after surgery was 8.84% (±5.32). One implant was lost before loading. All the 18 remaining osseointegrated implants received the prosthetic rehabilitation and were controlled after 3 months of functional loading. The implant survival rate at the 1-year interval was 94.74%. A 100% NanoBone alloplastic graft used in lateral SFE procedures presented limited height shrinkage. Implants placed in these grafted sinuses showed survival rates similar to those found in published data. These results should be interpreted cautiously considering the study's reduced sample size.

Cementum status in natural teeth opposing implant-borne bridgework in Macaca fascicularis

The objective of this study was to investigate the cementum status in natural teeth opposing implant-supported bridgework. Maxillary premolars and molars opposing immediate-loading (IL) and delayed-loading (DL) mandibular implant-supported bridgework in 4 Macaca fascicularis were harvested after 3 months of functional loading. Another 2 monkeys without mandibular fixed prostheses served as control. The cervical (CCW) and apical cementum width (ACW), and resorption craters (RCs) were measured. No significant differences were observed between test and control groups for mean CCW (control = 26.79 ± 3.28, IL = 21.29 ± 9.12, and DL = 20.32 ± 5.65 μm) and for ACW (control = 937.97 ± 353.74, IL = 955.26 ± 720.05, and DL = 750.56 ± 517.26 μm) (P > .05). In test and control monkeys, RCs were uncommon and showed no significant differences in width (control = 0.71 ± 0.38, IL = 1.02 ± 0.49, DL = 0.85 ± 1.02 mm) and depth (control = 0.15 ± 0.07, IL = 0.25 ± 0.40, DL = 0.22 ± 0.15 mm) (P > .05). Present findings suggest that implant-supported bridgework does not produce any adverse effects on the cementum of opposing natural teeth after 3 months of functional loading.